Thousands of people, many from California and some toting unloaded guns for sale, waited in line for nearly two hours across from Reno's glitzy Atlantis Hotel on a recent Saturday for the chance to buy and sell weapons. It is a right, they insisted, that never has been in greater jeopardy in America.

The crowd was the largest in memory for the Crossroads of the West gun show in Reno, organizers said, and the reason was hardly a mystery. Gun advocates are nervous amid talk of proposed laws that could restrict their ability to buy and sell weapons and ammunition. Already, several noted, gun shops across the country are reporting shortages.

"Why are there so many people here today?" asked Ellis Davis of Susanville, just west of the Nevada border, marveling at a line that stretched a quarter of a mile around the convention center. "Because they want to take away our gun rights."

The push for federal gun legislation is designed in part to deal with disparities among states with stricter gun laws and those that allow for purchase of a wider array of weapons with far less scrutiny.

Disparate gun laws make it easier for residents of California, for example, to travel to Nevada to buy just about any weapon they choose without undergoing background checks. The issue is a topic of discussion in Congress and among state lawmakers across the country.

California's laws are among the most stringent in the country. Only seven states, including California, ban the sale of large-capacity magazines. Eleven states, California included, require waiting periods of up to two weeks between the purchase of a gun and the transfer of the gun. The other 39 have no waiting periods.

President Barack Obama and the Congressional Gun Violence Prevention Task Force are calling for, among other things, requiring background checks for every gun sale. Today, many people buying firearms do not undergo such checks because federal law requires them only when someone buys a gun from a licensed dealer.

Obama's team also is calling for legislation that would crack down on illegal gun trafficking and "straw purchasing," in which a man or woman with no criminal history buys guns for someone who is barred from owning them. Lawmakers have yet to lay out specifically what type of legislation might be effective in stopping the practice.

And they are pressing to reinstate and strengthen a federal ban on assault weapons that can fire many shots in a short time. That ban expired in 2004, and efforts to revive it have failed repeatedly.

Leading the charge on Obama's behalf is Rep. Mike Thompson, a St. Helena Democrat and gun owner who is a former co-chair of the Congressional Sportsman Caucus.

Thompson, a hunter and combat veteran who carried an assault rifle in Vietnam, argues that tough restrictions in individual states are not enough to prevent criminals from getting guns. Californians flock to gun shows in Nevada, he said, where in private sales background checks are not required. He contends some of those guns turn up at crime scenes.

Statistics from the Bureau of Alcohol, Tobacco, Firearms and Explosives back him up. The federal agency traced the source of 50,000 weapons used in California during crimes from 2009 to 2011 and found that roughly a fourth of those guns came from outside the state. Nevada and Arizona were, by far, the leading suppliers, accounting for roughly a third of out-of-state weapons used in crimes.

National background checks and other federal restrictions, Thompson said, would "make it real tough" for criminals, people with documented mental problems or anyone else to procure weapons outside their home states.

But not everyone is supportive. Historically, Nevada residents and their leaders, particularly those outside of Las Vegas, have resisted gun control efforts.

In response to fears that Obama will unilaterally dictate who can own a gun, Jim Wheeler, a Republican Nevada assemblyman from Gardnerville, near Lake Tahoe, has introduced a bill that says the state attorney general must defend anyone arrested as a result of a presidential executive order that violates the Second Amendment.

"To me, about any law is too many laws," Wheeler said.

Stockton killings spurred action

Before Sandy Hook Elementary in Connecticut there was Cleveland Elementary in Stockton.

In 1989, a drifter armed with an AK-47 rifle peppered Cleveland Elementary with bullets that killed five children and wounded 30 others. A year later, California passed its ban on possession of semi-automatic assault weapons. Since then, state lawmakers have tightened restrictions in a range of areas, from who can buy guns to how and where they can be purchased.

In California, gun buyers must obtain their weapons from a licensed dealer and wait 10 days to get them. That "cooling off" period helps prevent gun violence committed in the heat of emotion, advocates argue.

In addition, names of gun buyers in California are checked against the National Instant Criminal Background Check System database. Federal law bars various people, including felons and those with documented mental illness, from buying weapons.

Serial numbers of guns purchased in California are registered with the Department of Justice, which allows police to trace them if they are used in crimes.

On the heels of the Sandy Hook shootings late last year, some state legislators want to get even tougher on gun owners.

Sen. Leland Yee, D-San Francisco, is carrying a bill that would make it harder to alter military-style weapons to be loaded with high-capacity magazines.

Other proposed measures include a tax on ammunition sales, an expansion of the definition of banned assault weapons, and a requirement that residents obtain a permit before buying ammunition.

The permit proposal, which police argue could help lead them to illegal weapons, is among the most controversial. Currently, only Sacramento and Los Angeles have ordinances barring ammunition sales to people with criminal records.

Yee cited studies showing that states with the toughest gun laws, including California, have the lowest per-capita rates of gun-related deaths.

"It's a fact that gun laws work and weak laws result in the loss of innocent lives," he said. "Clearly, there is a direct correlation between common-sense gun laws and fewer gun-related homicides."

A different mind-set has set the standard for gun ownership in California's neighbor to the east, where Nevada residents are governed by some of the most liberal weapons laws in the nation.

There, private citizens can go to gun shows and yard sales and legally buy and sell weapons to other state residents. No background checks are required, nor are guns registered with the state, with the exception of Clark County, which includes Las Vegas.

And unlike California, Nevadans can buy and sell machine guns capable of firing a large number of shots in rapid succession.

As in California, the loss of 20 young children in the Sandy Hook shooting has prompted some Nevada lawmakers to call for stricter regulations. The proposals making their way through the state Legislature include requirements for statewide gun registration and an excise tax on guns and ammunition that would fund mental health treatment.

But in Nevada, such measures are anything but slam dunks.

Wheeler, the Gardnerville assemblyman, said he doubts stricter gun laws will pass in Nevada anytime soon, noting that a law streamlining who can carry a concealed weapon just cleared a state Senate committee.

"The culture is different," he said, describing an independent streak that drives Nevadans to find their own way. Most gun control efforts, he noted, originate in urban areas.

"I grew up in L.A. In California, you have a lot of huge cities. We don't. We have one huge city, one medium-sized city and the rest are small."

Californians flock to Reno show

Outside the Reno Convention Center, where dozens of gun and ammunition dealers hawked their wares at the Crossroads of the West gun show last month, the buzz also was about laws.

Waiting for the doors to open, Ellis Davis, the Susanville resident, sported a baseball cap with the words, "Keep Guns In The Right Hands: YOURS." He opined that the nation has more laws than it needs, especially with regard to guns.

"It's not me shooting and robbing people," said Davis, a retired corrections officer. "It's the criminals. We've got a right to protect our homes and our families."

Based on attendance at the Reno show, many Californians share his view. At least a third of the cars parked around the convention center carried California plates.

Californians can buy weapons from dealers at such events, but by law are supposed to have them shipped across state lines, where the guns are processed through registered dealers. In private transactions, Nevada sellers by law cannot knowingly sell guns to Californians.

But many at the Reno event acknowledged that, especially in private transactions, both parties sometimes look the other way.

"There's no law that tells me I can't sell to someone from California," said one Nevada resident hoping to pick up some cash for a semi-automatic weapon he carried in his backpack. "It's not on me if they drive over to the communist side with this thing. It's on them." He declined to give his name.

By noon on the first Saturday of the Reno gun show, about 5,000 people had purchased tickets – more patrons than typically show up over the entire two-day event, said organizer Todd Johns.

"This is about the busiest show we've ever had," Johns said. At other shows in the western United States, "attendance has doubled and even tripled" in recent months, he said.

Despite the large crowds, the scene was calm as patrons filed into the convention hall. Those carrying guns turned them over to security personnel, who checked to see they were unloaded and disabled the triggers with plastic attachments.

Once inside, many gun owners bolted for the ammunition lines, while others perused dozens of tables featuring new and used guns, antique knives and gun-themed T-shirts and jewelry. Cowboy hats, camouflage wear and NRA caps were in abundance, along with $7 beers sold just outside the room.

Private sellers huddled, trading information about weapons and exchanging cash, while more than two dozen licensed dealers did a brisk business selling shotguns, handguns and semi-automatic rifles. Routinely, the licensed dealers asked for proof of Nevada residency.

Nevada resident Joe Potseaga was among those trying to cut a private deal. Like others, he worked the room with a semi-automatic rifle slung around his back and a cardboard sign advertising it for sale.

Potseaga, who said he takes part in sanctioned shooting competitions, sold a pistol to a fellow Nevadan. He said he respects the law when conducting private sales, and believes most others do the same.

"I wouldn't just hand it over for cash to someone from California," even if the price were right, he said.

Potseaga said his pistol buyer produced identification and "compelling proof that he is not a criminal and could lawfully own a weapon." The compelling proof? "His word," Potseaga said.

Prosecutions can be challenge

Graham Barlowe has spent a career enforcing California's gun laws as an agent for the federal Bureau of Alcohol, Tobacco, Firearms and Explosives. He contends the controls break down if California residents can drive a few hours and flout the state's gun laws.

"Different states have different standards," said Barlowe, Sacramento's agent in charge for the ATF. "It's impossible for the states with more restrictive standards to maintain them if someone can get around them by going to another jurisdiction."

In one pending federal case, a San Bernardino County resident is accused of buying 22 handguns at pawn shops in Las Vegas over a year using a fraudulent Nevada identification card. The man was caught after he listed his California address when registering the gun.

In another case, a woman working for a Carson City brothel bought four identical handguns in Nevada then drove to Sacramento, where she reported them stolen.

"The guns started turning up in the hands of gang members," Barlowe said.

Prosecuting illegal gun cases can be a challenge, said Barlowe, because of limited resources in district attorneys' offices and the conservative bent of juries in states where gun laws are more lenient.

"The jury of their peers is in Nevada," where the sales take place, he said, and most likely would have differing views about guns than Californians.

"It's very hard. You are just not going to see a large number of prosecutions."

Benjamin Wagner, U.S. attorney for the Eastern District of California, said his office has recently prosecuted cases involving "straw buyers" purchasing guns for criminals.

"We are very much aware that there are firearms that flow from Nevada to California in violation of federal law," Wagner said. But his office mostly focuses on major gun traffickers.

In recent weeks, Thompson has been busy selling his package of gun measures to constituents and news media in California and colleagues in Washington. He said he believes Americans are ready for tightening laws that curb gun violence while "protecting the Second Amendment right to own firearms."

"I am working to make sure Congress acts, and I am confident we will act," he said.

Yet he knows the proposals will be a tough sell to many around the country.

"If you do a lot of background checks, a lot of this stuff will take care of itself," Thompson said. But, he added, "I'm not going to give up my guns, and I'm not expecting anyone else to give up theirs."

Joe Potseaga and his cousin Andrew aren't buying it.

Like many at the Reno show, they said they resent politicians who want to intrude into matters they feel are already addressed by the Constitution.

"We love our country dearly," said Andrew Potseaga. "But it's none of the federal government's business knowing what kinds of guns people have."

GUN CONTROL PROPOSAL

Following the mass school shooting in Connecticut, a group of U.S. lawmakers, with the backing of President Barack Obama, has proposed a package of laws that would further limit access to guns. The group, spearheaded by Rep. Mike Thompson, D-St. Helena, cites a Supreme Court ruling that "the right secured by the Second Amendment is not unlimited," and that universal laws are critical to protecting the public.

Among the group's proposals:

A reinstatement of the expired federal ban on assault weapons, which the task force argues are "a lethal threat to law enforcement and other first-responders."

Reinstatement of a ban on assault weapons magazines that carry more than 10 rounds.

Strengthening the national database for background checks. The task force wants to crack down on federal agencies that have been lax in transferring records to the database.

Requiring a background check for every gun sale, with "reasonable exceptions" such as gifts between family members and temporary loans for sporting purposes.